There has been a growing debate
about the proper way to integrate science and theology. On the one side are
those who accept a complementarity view of integration and claim that science
must presuppose methodological naturalism. On the other side are those who
accept some form of theistic science. Central to this debate is the nature of
divine and human action and the existence of gaps in the natural causal fabric
due to such action that could, in principle, enter into the use of scientific
methodology. In this article, I side with the second group. To justify this
position, I first state the complementarity view and its implications for the
nature of human personhood, second, explain libertarian agency in contrast to
compatibilist models of action, and third, show why "gaps are part of
divine and human agency and illustrate ways that such a model of agency for
certain divine acts could be relevant to the practice of science.

The relationship between science and miracles contains many aspects
that are worthy topics of study in their own right. Currently, however, there
has been a growing and sometimes heated dialogue about the proper way to view
the integration of science and theology. A major part of this dialogue is a
debate between those who accept the idea that science must presuppose
methodological naturalism and those who reject this notion. The different camps
in this dispute accept very different ways of viewing the nature of a direct,
miraculous act of God and its relationship to the practice of science. Given the
ideological importance of science in contemporary culture, it is not surprising
to see naturalists claim that miracles, even if they happened, are totally
outside the limits of scientific theory formation, explanation, and confirmation
and, thus, are unscientific in this sense. For example, atheist philosopher
Michael Ruse claims that "even if scientific creationism were totally successful
in making its case as science, it would not yield a scientific explanation
of origins. Rather, at most, it could prove that science shows that there can be
nonscientific explanation of origins."1 Elsewhere, Ruse asserts
that "The Creationists believe the world started miraculously. But miracles lie
outside of science, which by definition deals with the natural, the repeatable,
that which is governed by law."2 What I find surprising is the fact
that a significant number of Christian intellectuals agree with this position.

Let us define
theistic science as a viewpoint which includes a commitment to the following
three propositions:3

1.God, conceived of as a personal,
transcendent agent of great power and intelligence, through direct, immediate,
primary agency and indirect, mediate, secondary causation created and designed
the world for a purpose. He acted directly through immediate, primary agency in
the course of its development at various times (including prehistory - history
prior to the arrival of human beings).4

2. The commitment expressed in
Proposition 1 can appropriately enter the very fabric of the practice of science
and the use of scientific methodology.

3. One way this commitment can
appropriately enter the practice of science is through various uses in
scientific methodology of gaps in the natural world. These gaps are essential
features of direct, immediate, primary divine agency properly understood.

The Christian
intellectuals mentioned above reject theistic science because, among other
things, it supposedly uses an inappropriate god-of-the-gaps strategy for doing
science and integrating it with theology. Instead, science requires the adoption
of methodological naturalism, the idea that science must study natural
(physical) entities from a natural point of view and seek explanations for
things in terms of natural events and laws that are part of the natural causal
fabric of the spatio-temporal world. Thus, theological beliefs in general, and
direct, immediate, miraculous acts of God lie outside science, properly
understood. The proper way to integrate science and theology is to view them as
non-interacting, complementary approaches to the same reality; as such, they
adopt very different standpoints, ask and answer very different kinds of
questions, involve different levels of description, employ very different
cognitive attitudes (e.g., objectivity and logical neutrality in science,
personal involvement and commitment in theology), and are constituted by very
different language games. These different, authentic perspectives are incomplete
and, therefore, must be integrated into a coherent whole. But, each level of
description (e.g., the chemical vs. the theological) is complete at its own
level, with no gaps at that level for other perspectives to fill, and with no
possibility for direct competition, conflict, or mutual epistemic reinforcement.5

I do not agree with
this perspective if it is taken as the total picture of science/theology
integration. In my view, theistic science is a legitimate research program. I
have defended my views elsewhere and cannot undertake here a general treatment
of this controversy.6 Instead, I shall focus on Proposition 3 above
and defend the idea that a certain understanding of agency theory shows that the
complementarity view is inadequate and that libertarian, agent acts (human and,
in some cases, divine) leave gaps in the causal fabric of the natural world that
could play a role in the practice of science. In what follows, I will, first,
state the complementarity view; second, explain libertarian agency in contrast
to compatibilist models of action, and third, show why "gaps" are part of such
agency and illustrate ways that such a model of agency for certain divine acts
could be relevant to the practice of science.

The Complementarity View

Currently, the
complementarity view enjoys wide popularity among both Christian and
non-Christian intellectuals. Among its Christian proponents are D. M. Mackay,7
A. R. Peacocke,8 Richard Bube,9 Howard J. Van Till,10
Paul de Vries,11 and David G. Myers.12 While scholars
differ about certain details of this approach, nevertheless, there is broad
agreement among them regarding the following components.

The Nature of Science

The goal of natural
science is to study the spatiotemporal natural world of matter and energy and
seek natural explanations for the physical properties, behavior, and formative
history of the physical universe. The very nature of natural science requires
one to adopt methodological naturalism, the idea that explanations of phenomena
are to be sought within the non-personal causal fabric of events and processes in
the created order. For example, in describing how two charged electrodes
separate hydrogen and oxygen gas when placed in water, the "God hypothesis" is
both unnecessary and out of place. In general, an appeal to personal intentions
or actions of an agent, especially a supernatural one, violates the
methodological naturalism that constitutes proper scientific methodology.
Methodological naturalism is unrelated to metaphysical naturalism (the view that
the spatiotemporal world of physical entities open to scientific investigation
is all there is) because philosophical theses about the existence, nature, and
acts of God are beyond the limits of, and are complementary with, science.13

Reality: A Hierarchy of Systems
Standing in Part/Whole Relationships

In nature, wholes
are often more than the additive sum of their parts. Reality consists in a
hierarchy of different levels of systems or things that are parts of and give
rise to wholes (systems or things) at higher levels of organization due to the
complex interaction of the parts at lower levels. For example, ascending from
bottom to top through the hierarchy we have the following: energy, subatomic
entities, atoms, molecules, constituents of cells (e.g., organelles), cells,
biological systems (e.g., the respiratory system), whole biological organisms,
the psychological level, the sociological level, and the theological level. As
one ascends, each new level does not exist because some new entity has been
added "from the outside," but rather, because it emerges from the lower level
due to the complex interaction of parts at that level. For example,
psychological states emerge and supervene upon the brain and central nervous
system when the latter reaches a certain level of complexity needed to generate
such an emergence.14 There are different understandings of
supervenience.15 However, a generally accepted understanding of it
for properties runs as follows: Property P supervenes on property Q just in case
(1) P and Q are completely distinct properties in that neither P nor Q enters
the very being or constitution of the other; (2) P is ontologically dependent on
and determined by Q; (3) the relationship between P and Q is nonreductive; (4)
For any possible world in which some entity x exists, if x has Q then that is
sufficient for its having P; there cannot be two entities alike in having Q but
differing with respect to P. An entity cannot change in respect to P, cease to
be P, or become more or less P without changing in respect to Q.

In this view, human
persons are not genuine substances with natures, but rather, are property-things
(ordered aggregates) - structured collections of externally related parts with
emergent properties. To clarify this point, it will be helpful to step back for
a moment and compare two different metaphysical positions about two very
different kinds of wholes with parts: substances, understood in the classic
interpretation of Aristotle and Aquinas, vs. property-things or ordered
aggregates.16

According to the
traditional view, living organisms, historically, were taken to be paradigm
cases of substances. First, a substance is a thing which has or owns properties
but is not had by something more basic than it. Secondly, a substance is a deep
unity of parts, properties, and capacities at a point in time; it maintains
absolute sameness through (accidental) change. Substances are wholes that are
ontologically prior to their parts in that those parts are what they are in
virtue of what the substance is, taken as a whole. For example, a chamber of a
heart is defined in terms of the heart as a whole; the heart is defined in terms
of the circulation system as a whole; and the circulation system is defined in
terms of the organism as a whole. Thirdly, a substance is a this-such, i.e., an
individuated member of its natural kind which, in turn, constitutes its essence.
For example, two dogs are different, particular animals with the same nature.
The unity and nature of a substance derive from its essence that which lies
within it. Its parts (e.g., the nose and claws of a dog) stand in internal
relationship to each other in that if a part is removed from its whole, it loses
its identity with itself. As Aristotle said, a severed human hand is, strictly
speaking, no longer human - a fact that will become evident in a few days.

Substances are wholes
that are ontologically prior to their parts in that those parts are what they
are in virtue of what the substance is, taken as a whole.

An artifact, like a
table or automobile, is a paradigm case of a property-thing. Property-things
derive their unity from an external ordering principle (either in the mind of a
designer or from a law of nature) imposed from the outside on a set of parts to
form the object. A property-thing is structured stuff, i.e., parts placed in
some type of ordering relationship. In such wholes, the parts are prior to the
whole; the whole contains some sort of structural property that supervenes upon
those parts (it is defined in terms of the parts and the ordering relationship);
the parts are related to each other by means of external relationships; they
remain identical to themselves regardless of whether or not they are in the
whole property-thing (e.g., a car door is still what it is when detached from a
car); and property-things do not maintain strict identity through loss of old
parts or properties and gain of new ones.

Regarding human
persons in particular, philosophers widely agree that the following are
inconsistent with the property-thing position but are easier to justify on the
substance view (and, in fact, may have the substance view as a necessary
condition): the absolute unity of a person at a time; the irreducibility of the
first person perspective; the absolute sameness of a person through change; the
organic unity of the human body and the distinctive, irreducible, species
specific, law-like ways it changes through time; the irreducibility or
uneliminability of literal biological function or, more generally, teleology;
the metaphysical possibility (let alone the reality) of disembodied existence;
libertarian freedom; and the existence of human nature as that which constitutes
the unity of the class of all humans.17 I am not arguing that the
items on this list are real, though I take that to be the case. I do think,
however, that one should think carefully about how the complementarity
property-thing model of living organ-isms - more specifically, human persons -
has difficulty allowing for these things to be the case. One should ask whether
the complementarity view is intellectually worth the price of jettisoning these
arguably real aspects of human persons. Here is the main issue: the
complementarity view does not have the intellectual resources to allow for the
precise type of unity necessary for these features of human persons to obtain
and if they are, in fact, genuine, then the complementarity view's response to
reductionism is simply inadequate.

Interaction Between Levels

Each level in the hierarchy is capable
of an exhaustive description at that level using only concepts, theories, or
laws appropriate to that level. Such descriptions are complete with no gaps that
need to be filled in by theories or laws referring to entities, properties, or
processes at higher levels. For example, when a person chooses to eat fruit (a
good choice!), a complete description of that action can be given at each level
(e.g., the atomic, the psychological). Each level of description is an
authentic, though partial, perspective and the whole truth requires an appeal to
all the levels of description that are complementary to each other. Moreover, it
is interesting that the bottom level is the one studied by physicists. Lower
levels are more basic and sustain higher levels in existence. Higher levels
emerge upon and are determined by the entities and patterns of interaction at
lower levels. If some story is true at a higher level, then some story must be
true at a lower level but not vice versa.18 In general, some physical
(e.g., neurophysiological) state is necessary for a higher level (e.g., mental)
state to exist and when some specific physical state obtains, that is sufficient
for the occurrence of the supervening (e.g., mental) state.

We have just noted the relationship
among levels as far as sustaining something in existence is concerned. A closely
related, but distinct, issue involves the relationship of causality between
levels. Regarding causality, the first thing to note is this: events are what do
the causing in the natural world, i.e., events cause other events to occur. For
example, a brain event is the cause for a mental event. Secondly, a serious
problem to be probed later involves the causal efficacy (and not the reduction)
of higher levels of description, most important, the mental level.

In general, some
physical (e.g., neurophysiological) state is necessary for a higher level (e.g.,
mental)
state to exist and when some specific physical state obtains, that is
sufficient
for the occurrence of the supervening (e.g., mental) state.

Advocates of the
complementarity view appear to be caught in a dilemma. On the one hand, it is
hard to avoid treating higher levels of description as causally impotent
epiphenomena that supervene upon lower level systems because each lowest level
physical state is (1) complete at its own level of description and (2)
sufficient for the emergence of the higher level state. As philosophers Kathleen
Lennon and David Charles argue, the only way to accept a psychological level of
causal descriptions and also hold "that physical explanation is complete, i.e.,
that all physically characterizable events are susceptible to explanation on
terms of physically sufficient cause...is to accept
[the] reduction [of the psychological to the physical]."19 On the
other hand, in spite of the apparent inconsistency in doing so, advocates of
this view allow that when higher level entities emerge, then events at that
level can cause events to occur at lower levels through feedback mechanisms and
event-event causation. As Jaegwon Kim has shown, the problem here is that "downward
causation prima facie implies the failure of causal closure at the lower
level, and the in principle impossibility of a complete theory of the
lower-level phenomena in their own terms."20 The question here is
not that such feedback occurs, but whether there is room within the
complementarity view for its occurrence that does not have an air of ad hoc-ness
about it.

Agency and Free Will

Later, I will
clarify the difference between libertarian and compatibilist views of freedom
and agency. But for now, it should be noted that the complementarity view
eschews libertarian freedom and agency in favor of compatibilist models of
freedom. An illustration may help us understand the complementarity view.
Consider the act of raising one's hand to vote. At the various levels of natural
science, a complete account of such an act could be given in terms of biological
systems, neurons, brain states, etc. These levels of description would be
ignorant of the psychological level in the sense that they would be what they
are, with or without the presence of the higher psychological level, and they
would contain no reference to mental processes, events, properties, etc. But a
complete, noninteracting account of the act could be given at a psychological
level by appealing to the individual's desire to vote, his belief that raising
his hand would satisfy this desire, and his willingness to raise his hand.
Personal agency and action fall completely outside natural science levels of
description, complementary to the psychological level.

Divine Action and Creation's Functional
Integrity

If we set aside
human history, especially salvation history in which God performed primary
causal miraculous acts, like parting the Red Sea or raising Jesus of Nazareth
from the dead, then a consistent picture of divine action in the natural world
emerges from what has already been said. God is not to be seen as a direct,
primary, causal agent who suspends or overrides the laws of nature (by acting in
a way different from his normal, regular activity), creating a gap in the
natural fabric. Rather, God is constantly active in each and every event that
happens. God sustains natural processes in existence, and expresses his freedom
to act by employing natural processes mediately as secondary causes to
accomplish his purposes in the world.21 He works "in and through"
the natural causal fabric, unfolds its potentialities according to deterministic
or probabilistic laws of nature and he does so without leaving any causal gaps in
lower level physical processes and systems. God is the ground of all causes and
the ultimate cause of all things. Moreover, God's acting in and through natural
events can be understood as the meaning and purposive pattern that can be seen
in the providential unfolding of those events. As Howard J. Van Till puts it,
God has created the world with functional integrity:

By this term I
mean to denote a created world that has no functional deficiencies, no gaps in
its economy of the sort that would require God to act immediately, temporarily
assuming the role of creature to perform functions within the economy of the
created world that other creatures have not been equipped to perform.22

God-of-the-Gaps

Advocates of the
complementarity view have a disdain and loathing for what is called a
god-of-the-gaps argument. According to many complementarians, this type of
argument is an epistemically inappropriate strategy in which God only acts when
there are gaps in nature; one appeals to God merely to fill gaps in our
scientific knowledge of naturalistic mechanism; these gaps and the appeal to God
just mentioned are used in apologetic, natural-theology arguments to support
Christian theism; and God is manifest and proved only by the miraculous, by that
which defies natural scientific explanation. This strategy is bad for at least
two reasons. First, natural science is making these gaps increasingly rare and,
thus, there is less need to believe in God if such a belief is justified solely
or largely by the god-of-the-gaps strategy. Secondly, this strategy is based on
a faulty understanding of the integration of science and theology and the proper
model of human and divine action as depicted in the complementarity model. In
particular, the strategy fails because there simply are no such gaps in the
natural world, given the views already presented in this section.

I have responded to
this argument elsewhere, and I will address it later in this article.23The
argument represents a caricature of advocates of theistic science who see gaps
in the natural world due to direct acts of God which can, in principle, be
relevant to scientific methodology. No advocate of theistic science claims that
God only acts in the "gaps." God is constantly active in sustaining the
world, in concurring with natural processes, and the like. But advocates of
theistic science believe that there is a scientifically and epistemically
relevant distinction between primary and secondary causality and that both types
of actions are relevant to the task of integrating science and theology. Belief
in such a gap (and an appeal to a primary causal act of God to explain it)
should not merely be based on ignorance of a natural causal mechanism, but on
positive theological, philosophical, or scientific arguments that would lead one
to expect such a gap. While most advocates of theistic science do use such a
strategy for positive apologetic purposes, such a purpose is not necessary for
an advocate of theistic science. If apologetic purposes are part of a person's
employment of theistic science, then that person need not hold that the entire
ground for justifying belief in God is the explanatory work that "the God
hypothesis" does in explaining gaps. Thus, most critical discussions of
god-of-the-gaps issues generate far more heat than light precisely because they
represent a gross caricature of those who actually employ this strategy.

The real issue is
this: if God acts as a primary causal agent distinct from his action as a
secondary cause, does it follow that there will be miraculous gaps in the
natural causal fabric that could, in principle, be relevant to scientific
methodology? I believe that the answer is "Yes," and to see why, we now
turn to the difference between libertarian and compatibilist views of freedom
and agency. Because the natures of freedom and agency are so central to the
reality of causal gaps and theistic science, I must go into some detail in
describing these competing models.

Libertarian and Compatibilist Models
of Agency

All Christians
believe we have free will, but they differ about what free will is. We can
define determinism as the view that for every event that happens, there are
conditions such that, given them, nothing else could have happened. Every event
is caused or necessitated by prior factors such that given these prior factors,
the event in question had to occur. Libertarians embrace free will and hold that
determinism is incompatible with it. Compatibilists hold that freedom and
determinism are compatible with each other and, thus, the truth of determinism
does not eliminate freedom. As we will see, compatibilists have a different
understanding of free will from the one embraced by libertarians and hard
determinists.

General Comparison

1. Compatibilism. For
compatibilists, if determinism is true, then every human action (e.g., raising
one's hand to vote) is causally required by events that obtained prior to the
action, including events that existed before the person acting was born. That
is, human actions are mere happenings, parts of causal chains of
events leading up to them. Freedom properly understood, however, is compatible
with determinism.

2. Libertarianism.
Libertarians claim that the freedom necessary for responsible action is not
compatible with determinism. Real freedom requires a type of control over one's
action - and, more important, over one's will - such that, given a choice to do A
(raise one's hand and vote) or B (leave the room), nothing determines that
either choice is made. Rather, the agent himself must simply exercise his own causal
powers and will to do one alternative, say A (or have the power to refrain
from willing to do something). When an agent wills A, he also could have willed
B without anything else being different inside or outside of his being. He is
the absolute originator of his own actions. When an agent acts freely, he is a first
or
unmoved mover; no event causes him to act. His desires, beliefs, etc. may
influence his choice, but free acts are not caused by prior states in the agent.

Suppose we have
person P that freely did some act e, say changing his thoughts or raising his
arm. A more precise, initial characterization of libertarian freedom and agency
can be given as follows:

1.P is a substance that had the power
to cause e.

2.P exerted its power as a first mover
(an uncaused cause of action) to cause e.

3.P had the ability to refrain
from exerting its power to cause e.

4.P caused e for the sake of some
final cause, R, which is the reason P caused e.

We can delve more deeply into
compatibilist and libertarian accounts of freedom by looking at four areas
central to an adequate theory of free will.

Four Areas of Comparison Between
Compatibilism and Libertarianism

1. The Ability Condition.
To have the freedom necessary for responsible agency, one must have the ability
to choose differently from the way the agent actually does. Compatibilists and
libertarians agree that a free choice is one where a person "can" will to
do otherwise but differ about what this ability is. Compatibilists see this
ability as a hypothetical ability. Roughly, this means that the agent would have
done otherwise had some other condition obtained, e.g., had the agent desired to
do so. We are free to will whatever we desire though our desires are themselves
determined. Freedom is willing to act on your strongest preference.

Libertarians view hypothetical ability
as a slight of hand and not sufficient for the freedom needed for responsible
agency. For libertarians, the real issue is not whether we are free to do what
we want, but whether we are free to want in the first place. A free act is one
in which the agent is the ultimate originating source of the act. Freedom
requires that we have the categorical ability to act, or at least, to will to
act. This means that if Smith freely does (or wills to do) A, he could have
refrained from doing (or willing to do) A or he could have done (or willed to
have done) B without any conditions whatsoever being different. No description
of Smith's desires, beliefs, character, or other things in his makeup and no
description of the universe prior to and at the moment of his choice to do A is
sufficient to entail that he did A. It was not necessary that anything be
different for Smith to do B instead. This means that there will be a gap in the
universe just prior to and after a free act due to the causal activity of the
agent as first mover.

Compatibilists
and libertarians agree that a free choice is one where a person "can"
will to do otherwise but differ about what this ability is.

The libertarian
notion of categorical ability includes a dual ability: if one has the ability to
exert his power to do (or will to do) A, one also has the ability to refrain
from exerting his power to do (or will to do) A. By contrast, the compatibilist
notion of hypothetical ability is not a dual ability. Given a description of a
person's circumstances and internal states at time t, only one choice could
obtain and the ability to refrain is not there; its presence depends on the
hypothetical condition that the person had a desire (namely, to refrain from
acting) which was not actually present. There is no causal gap just prior to and
after the act of a substantial first mover who contributes causal power into the
natural causal fabric because this view of agency is rejected by compatibilists.

2. The Control Condition.
Suppose Jones raises his hand to vote. Compatibilists and libertarians agree
that a necessary condition for the freedom of this act is that Jones must be in
control of the act itself. However, they differ radically about what control is.

To understand
compatibilist views of the control condition, recall that compatibilists take
cause and effect to be characterized as a series of events making up causal
chains with earlier events and the laws of nature (either deterministic or
probabilistic) causing later events. The universe is what it is at the present
moment because of the state of the universe at the moment before the present and
the correct causal laws describing the universe. A crude example of such a
causal chain would be a series of 100 dominos falling in sequence from the first
domino on until domino 100 falls. Suppose all the dominos are black except
numbers 40-50, which are green. Here we have a causal chain of events that
progresses from domino one to 100 and that "runs through" the green
dominos.

According to
compatibilism, an act is free only if it is under the agent's own control. And
it is under the agent's own control only if the causal chain of events - which
extends back in time to events realized before the agent was even born - that
caused the act (Jones's hand being raised) "runs through" the agent
himself in the correct way. But what does it mean to say that the causal chain "runs
through the agent in the correct way"? Here compatibilists differ from each
other. But the basic idea is that an agent is in control of an act, just in case
the act is caused in the right way by prior states of the agent himself (e.g.,
by the agent's own character, beliefs, desires, and values). This idea is
sometimes called a causal theory ofaction.

Libertarians reject the causal theory
of action and the compatibilist notion of control and claim that a different
sense of control is needed for freedom to exist. Consider a case where a staff
moves a stone but is itself moved by a hand that is moved by a man. In Summa
contra GentilesI, Chap. 8, St. Thomas Aquinas states a principle about
causal chains that is relevant to the type of control necessary for libertarian
freedom:

In an ordered
series of movers and things moved [to move is to change in some way], it is
necessarily the fact that, when the first mover is removed or ceases to move,
no other mover will move [another] or be [itself] moved. For the first mover
is the cause of motion for all the others. But, if there are movers and things
moved following an order to infinity, there will be no first mover, but all
would be as intermediate movers.... [Now] that which moves [another]
as an instrumental cause cannot [so] move unless there be a principal moving
cause [a first cause, an unmoved mover].

Suppose we have nine
stationary cars lined up bumper to bumper and a tenth car runs into the first
car causing each to move the next vehicle until car nine on the end is moved.
Suppose further that all the cars are black except cars 5 to 8 which are green.
Now, what caused the ninth car to move? According to Aquinas, cars 2 to 8 are
not the real cause of motion for car 9. Why? Because they are only instrumental
causes, each of these cars passively receives motion and transfers
that motion to the next car in the series. Car 1 (actually, the driver of car 1)
is the real cause since it is the first mover of the series. It is the source of
motion for all the others. Only first movers are the sources of action, not
instrumental movers that merely receive motion passively and pass that on to the
next member in a causal chain.

Compatibilists and
libertarians agree that a necessary condition for the freedom [to] act is that
[a person]
must be in control of the act itself. However, they differ radically about
what control is.

For libertarians, it
is only if agents are first causes, unmoved movers, that they have the control
necessary for freedom. An agent must be the absolute, originating source of his
own actions to be in control. If, as compatibilists picture it, an agent is just
a theater through which a chain of instrumental causes passes, then there is no
real control. Further, the control that an unmoved mover exercises in free
action is a dual control " it is the power to exercise his own ability to act or
to refrain from exercising his own ability to act.

3. The Rationality Condition.
The rationality condition requires that an agent have a personal reason for
acting before the act counts as a free one.24 Consider again the case
of Jones raising his hand to vote. In order to understand the difference between
the two schools about how to handle this case in light of the rationality
condition, we need to draw a distinction between an efficient and a final
cause. An efficient cause is that by means of which an effect is
produced. One ball moving another is an example of efficient causality. By
contrast, a final cause is that for the sake of which an effect is produced.
Final causes are teleological goals, ends, or purposes for which an event is
done; the event is a means to the end that is the final cause.

Now a compatibilist will explain Jones' voting in terms of efficient and not
final causes. According to this view, Jones had a desire to vote and a belief
that raising his hand would satisfy this desire and this state of affairs in him
(the belief/desireset composed of the two items just mentioned) caused the state of affairs of his
hand going up. In general, whenever some person S does A (raises his hand) to do
B (vote), we can restate this as S does A (raises his hand) because he desired
to B (vote) and believed that by A-ing (raising his hand), he would satisfy
desire B. On this view, a reason for acting turns out to be a certain type of
state in the agent, a belief-desire state, that is the real efficient cause of
the action taking place. Persons as substances do not act; states within persons
cause latter states to occur. The compatibilist, in possession of a clear way to
explain cases where S does A to do B, challenges the libertarian to come up with
an alternative explanation.

Many libertarians
respond by saying that our reasons for acting are final and not efficient
causes. Jones raises his hand in order to vote, or perhaps, to satisfy his
desire to vote. In general, when person S does A to do B, B states the reason
(e.g., a desire or a value) which is the teleological end or purpose for the
sake of which S freely does A. Here the person acts as an unmoved mover by
simply exercising his powers in raising his arm spontaneously. His beliefs and
desires do not cause the arm to go up; he himself does. But B serves as a final
cause or purpose for the sake of which A is done. Thus, compatibilists embrace a
belief/desire psychology (states of beliefs and desires in the agent cause the
action to take place), while at least many libertarians reject it and see a
different role for beliefs and desires in free acts.

4.Causation . From what has
already been said, we can anticipate a difference between libertarians and
compatibilists about causation. For the compatibilist, the only type of
causation is called event-event causation. Suppose a brick breaks a glass. In
general, event-event causation can be defined in this way: an event of kind K
(the moving of the brick and its touching of the surface of the glass) in
circumstances of kind C (the glass being in a solid and not liquid state)
occurring to an entity of kind E (the glass object itself) causes an event of
kind Q (the breaking of the glass) to occur. Here, all causes and effects in the
chain are events. If we say that a desire to vote caused Jones to raise his arm
we are wrong. Strictly speaking, a desiring to vote caused a raising of the arm
inside of Jones.

Libertarians agree that event-event
causation is the correct way to account for normal events in the natural world,
like bricks breaking glasses. But when it comes to the free acts of persons, the
person, as a substance and an agent directly produces the effect. Persons are
agents and, as such, in free acts they either cause their acts for the sake of
reasons (called agent causation) or their acts are simply uncaused events they
spontaneously do by exercising their powers for the sake of reasons (called a
noncausal theory of agency). Either way, persons are seen as first causes,
unmoved movers who have the power to exercise the ability to act as the ultimate
originators of their actions. It is the I, the self that acts; not a state in
the self that causes a moving of some kind. Libertarians claim that their view
makes sense of the difference between actions (expressed by the active voice,
e.g., Jones raised his hand to vote) and mere happenings (expressed by the
passive voice, e.g., a raising of the hand was caused by a desiring to vote,
which was caused by x, ...).

For the compatibilist,
the only type of causation is called event-event causation....[For the
Libertarian,]
when it comes to the free acts of persons, the person, as a substance and an
agent, directly produces the effect.

At this point it may
be helpful to discuss the relevance of quantum physics to the free will debate.
According to some, certain quantum events (e.g., the precise location of an
electron hitting a plate after being shot through a slit, the exact time a
specific atom of uranium will decay into lead) are completely uncaused events
and, as such, are indeterminate, random happenings. Thus, it is argued, a
quantum view of reality abandons determinism and makes room for freedom. As
chemist Michael Kellman puts it, "...the theory of quantum mechanics...is
compatible with a role for mind as agent in determining some actions of purely
material portions of biological systems."25

Unfortunately,
quantum physics has little relevance to the free will debate. For one thing,
many scientists believe that the quantum world is just as determined as the
regular world of macro-objects, like baseballs and cars. We just do not (perhaps
cannot) know what the causes are for some events and we cannot predict exactly
the precise behavior of quantum entities. For another thing, even if we grant
that the quantum world is really a place where determinism is false, it could
still be argued that determinism reigns in the macro world. More important, a
necessary condition of libertarian freedom is a view of the person as a
substance that acts as an agent, i.e., as a first cause or an unmoved mover.
Thus, determinism is sufficient for a denial of libertarian freedom, since it
says that all events are caused by prior events and there are no substantial
agents that act as unmoved movers. But determinism is not necessary to deny such
freedom. Completely uncaused events that randomly occur without reason (as in
the quantum world) do not give the type of agency needed for libertarian freedom
either. The main debate between compatibilists and libertarians is one about the
nature of agency and not determinism per se, although the truth of determinism
is sufficient for the denial of libertarianism as was already mentioned.

With this in mind,
we can modify the understanding of modern compatibilism we have used up to this
point. Compatibilism is basically the thesis that freedom and determinism are
compatible with each other, i.e., that both can be true. But some, indeed,
most compatibilists go on to accept the truth of determinism, while others do
not make a commitment to accepting determinism. However, both groups of
compatibilists reject libertarian agency. So while we will continue to focus on
the majority of compatibilists who accept determinism, we need to remember that
the nature of agency, and not determinism per se, is the main disagreement
between compatibilists and libertarians. Next let us apply these insights about
agency to questions regarding miracles, gaps, and theistic science.26

Miracles, Agent Gaps, and Science

Complementarian A.
R. Peacocke has said that the "problem of the human sense of being an
agent...acting in this physical causal nexus, is of the same ilk as the
relationship of God to the world."27 I agree. But whereas Peacocke
uses this point to support the complementarian view and place miracles outside
the bounds of science, I claim that the analogy between human and divine action
actually supports theistic science and the possibility of miraculous acts being
part of science. The difference between us is this: Peacocke and complementarian
methodological naturalists in general adopt compatibilist models of (divine and
human) action (at least for causality outside of salvation history) with the
result that no gaps exist in the causal fabric. I see (divine and human) action
in terms of libertarian agency and believe that free acts leave scientifically
detectable gaps in the natural world.

To see why
complementarian compatibilists have no room for gaps, consider the following
statements from naturalist philosophers. John Searle has said that "our
conception of physical reality simply does not allow for radical [libertarian]
freedom."28 The reason for this is that once
you claim that the physical level of description is both basic and complete, you
rule out the possibility of top-down feedback. As naturalist David Papineau has
argued:

I take it that
physics, unlike the other special sciences, is complete, in
the sense that all physical events are determined, or have their chances
determined, by prior physical events according to physical laws.
In other words, we never need to look beyond the realm of the physical in
order to identify a set of antecedents which fixes the chances of subsequent
physical occurrence. A purely physical specification, plus physical laws, will
always suffice to tell us what is physically going to happen, insofar as that
can be foretold at all.29

Jaegwon Kim says
that someone who holds that the physical level is basic and complete must "accept
some form of the principle that the physical domain is causally closed "that if
a physical phenomenon is causally explainable, it must have an explanation
within the physical domain."30Here is the reason for the
remarks by Searle, Papineau, and Kim. In every alleged case where there is a
description of top-down causation (e.g., where a state of intending to raise my
arm causes the raising of the arm), there will be a corresponding description of
a causal sequence of events that run along the bottom level (e.g., there will be
a physical state "associated with" the mental state of intending to raise one's
arm and a physical state "associated with" each moment of the arm being
raised).

Moreover, when we claim that the
physical is the bottom level, this means not just that each upper level event
has some lower level event or another correlated with it. It means that the
description of the bottom level sequence of events is complete without any gaps.
For example, at each moment during the process of voting - desire to vote,
believe that raising my arm will satisfy that desire, deliberate about whether
to vote, will to raise my arm, and raise it - throughout a time of a few
seconds, there will be a physical state in my brain and nervous system that is
sufficient to produce the next physical state without room for feedback.
Remember, the physical level description is complete and basic. There is no room
for mental entities to make a physical difference in the world because once the
physical antecedents are fixed, so are the physical consequences (or at least
their probabilities). This is simply what it means to claim that the physical is
both basic and complete at its own level of description. Moreover, each alleged
description of a top-down causal connection will have a description that runs
the other way and that is more consistent with the view that the physical level
is at the bottom. In any case, even if one allows for top-down
mental-to-physical feedback, this type of causality will still be event-event
causation with no room for libertarian agency.

Complementarian
methodological naturalists in general adopt compatibilist models
of...action...with the result
that no gaps exist in the causal fabric. I see...action in terms of libertarian
agency and believe that
free acts leave scientifically detectable gaps in the natural world.

By contrast, in
cases of libertarian action, say, just before one acts to raise one's arm and
during the raising of it, the description of one's brain and central nervous
system just before acting will not be sufficient to entail or causally account
for the physical description resulting from the agent's own (first mover)
exercise of causal power. Of course, at each moment there will be some physical
state, but the events at the physical level will not form a continuous chain of
causal events. Instead, there will be a causal gap due to the action of the
agent. This is why some have objected to libertarian agency since libertarian
acts violate the first law of the conservation of energy. I think such acts do
indeed violate the first law and, in fact, this is part of what it means for an
agent to be in the image of God - he or she is
capable of genuine creativity and novelty. Moreover, Robert Larmer argues that
we must distinguish two forms of the First Law. A strong form states that energy
can neither be created nor destroyed. A weak form states that in a causally
closed system, the total amount of energy remains constant. Larmer says that
libertarian agency is inconsistent with the strong, but not the weak, form
because the human body is not a causally closed physical system.31
He correctly sees that libertarian acts leave gaps in the natural causal fabric.

If we assume for a
moment that libertarian agency is the correct model of divine action for primary
causal miracles, then whenever God acts in this way, there will be a gap in the
natural world that could figure into scientific practice in at least three ways.
First, scientific methodology includes the psychology of discovery, roughly, the
psychological processes scientists go through to come up with theories to guide
their research. Now it is a known fact that in the history of science, a
hypothesis often has suggested itself to a scientist from his theological or
metaphysical beliefs. If someone held that various things in the natural world
were the result of a libertarian, miraculous act of God (e.g., the beginning of
the universe, the direct creation of first life and the various kinds of life,
the direct creation of human beings in the Mid-East, the flood of Noah), then
such a belief could guide a scientist in postulating that there will be no
natural explanation for the occurrence of these things. This could, in turn,
lead him or her to try to discover evidence for these events (the flood of Noah,
a Mid-Eastern origin for human beings) or to try to falsify the fact that they
were the result of miraculous acts by trying to discover natural mechanisms for
their occurrence that he or she believes are not there.

Secondly, in a
number of areas of science (forensic science, SETI, archeology, psychology),
scientific explanations for some phenomenon appeal to the desires, beliefs,
intentions, and actions of personal agents. Thus, for example, if one discovered
that living systems are discontinuous with nonliving systems in such a way that
living systems bear certain features that usually result from personal agency
(e.g., information in DNA, different kinds of design such as beauty, order,
etc.), and if one has grounds for thinking that it is improbable that a
naturalist mechanism will be found to account for this, then one could
legitimately see the origin of life as a gap in the history of the universe due
to a primary causal act of God. In this case, an appeal to divine action,
intentions, and so forth could be a legitimate form of scientific explanation.

Thirdly, these
features of living systems could lend some confirmation to the hypothesis that
life was, indeed, the result of a miraculous act of God. Such claims would be
defeasible (i.e., they could be shown false given more data), but this is
irrelevant, since all scientific theories are (in principle) defeasible. Yet
they are often well enough attested to be rationally accepted. In these three
ways - scientific discovery, scientific explanation that is a form of personal
explanation, and scientific confirmation - gaps in the causal fabric derived
from theological models of primary causal divine agency regarding some natural
phenomenon could enter into scientific methodology.32

Conclusion

In this article, I
have not had the space to defend libertarian agency for human or divine (primary
causal) action, though I obviously think such a defense is possible.
Fortunately, such a defense is not needed for my purposes here. I have tried to
show that the claim that miracles are in principle outside the bounds of science
is one embedded in a backdrop that includes a complementarian, methodological,
naturalist view of science and reality, along with a compatibilist view of human
and divine action in the natural world (outside salvation history). This, in
turn, has lead many to reject any version of a theistic explanation for gaps
because, among other things, the backdrop just mentioned denies that such gaps
exist.

Whether miracles are
outside the bounds of science, then, depends in part on one's model of divine
agency...

By contrast, I do
not limit the use of theistic science to the employment of explanations that
appeal to direct, primary causal acts of God. Nevertheless, if such acts have
occurred in certain cases, and if libertarian agency is a good model for
depicting such actions, then there will be gaps in the causal fabric that can
enter scientific practice. Whether miracles are outside the bounds of science,
then, depends in part on one's model of divine agency which, in turn, can be
understood from an analogy with human action. Complementarians may,
unfortunately, reject libertarian agency, but even if they do, I hope to have
made clear why some of us who accept this model believe that miracles can, in
fact, be part of scientific practice.

3Nothing honorific is meant
by the term "theistic science." More precisely, it is not meant to imply that
methodological naturalists are not solid Christian theists. The term is
currently being used to label a view bearing a family resemblance to the
definition I offer here. No emotional connotations should be derived from the
label.

4It has been argued that
Proposition 1 assumes that we know God has directly acted in the world from
insights about what a creator would do and that we should, instead, exhaust
every possible natural process for God's activity before concluding we have a
primary cause. Three things are wrong with this suggestion. First, any statement
of a theory or research program contains assertions in the indicative mood, and
such propositions do not imply anything whatever about commitment to the truth
of those propositions or the epistemic strength of such commitment. One can use
a theory to explore the natural world even if one wishes to falsify the theory.
The presence of 1 does not imply that anyone holds the assumption in question,
much less that someone knows it to be true. Second, even if one believes
proposition 1 to be true, why can't this believe rest, in part, on prior
theological or philosophical arguments. I see no reason to think that one must
exhaust every possible naturalistic explanation before one is justified in
believing 1. Even in science, a theory can receive some initial epistemic
support from so-called non-empirical factors (elegance, simplicity, internal
clarity, harmony with external conceptual problems), so such a prior commitment
does not violate the nature of science. Third, many advocates of theistic
science believe that we have, in fact, exhausted enough naturalistic
possibilities to justify the defeasible commitment to a primary causal divine
act for things like the origin of life or human beings.

5Richard Bube has complained
that my characterization of complementarity is confused and is actually a
description of what he calls compartmentalization. See his Putting It All
Together (Lanham, MD: University Press of America, 1995), 168. Cf. chapters 6
and 10. For Bube, compartmentalization treats science and theology as different
descriptions about different kinds of things with no common ground or
possibility of conflict. Complementarity views science and theology as different
descriptions of the same reality. Unfortunately, Bube is simply wrong in this
complaint toward my position. What he calls compartmentalization is close to
what I call the "two realms" view of integration and my description of
complementarity is an accurate one. The source of Bube's confusion is revealing.
I claim that the complementarity view eschews interaction between science and
theology and Bube says that it embraces such interaction. However, Bube
equivocates on what "interaction' means in this context. For me, it is "epistemic"
interaction, roughly the same description of the same reality that can be in
conflict or concord to varying degrees of strength. For Bube, interaction
amounts to taking two different (non-interacting in my sense) perspectives and
forming them into a whole. For example, a completely scientific description of
the origin of life in natural terms could be described in theological terms as
God's activity in bringing life into being. It is clear that his notion of
interaction is not the one I deny in explicating complementarity. Moreover, my
use of interaction is crucial in understanding the significance for scientific
methodology of gaps in the natural causal fabric due to libertarian agency and
primary causal activity on God's part.

13Howard J. Van Till has
complained that my description of methodological naturalism treats it as a
scientific strategy that begins with philosophical naturalism, strips away all
reference to atheistic metaphysics, and leaves room only for methodological
rules that proscribe consideration of divine action. According to Van Till, this
is a caricature. See "Special Creationism in Designers Clothing: A Response to The
CreationHypothesis
in Perspectives on Science and Christian Faith. 47 (June 1995): 126-27.
It should be clear, however, that I have done no such thing. I acknowledge that
Van Till and others distinguish philosophical from methodological naturalism.
The point is that for Van Till theological notions like primary causal acts of
God do not play a role within the methodology of science. If Van Till
thinks that this is a caricature, then he needs to point out where this
description is wrong and state where theological concepts have a role within
scientific methodology in his view.

14Advocates of the
complementarity view differ in the details here and, in some cases, appear to be
confused. Early on Peacocke advocated what is called type type identity
physicalism regarding the mental, Bube seems to embrace property dualism, and
Mackay appears to conflate a double aspect, a type type identity, and a
functionalist view of the mind/body problem. On Mackay, see Human Science &
Human Dignity, 26-34.

16For more on this see
Richard Connell, Substance and Modern Science, (Notre Dame: University of
Notre Dame Press, 1988). There are other uses of the term "substance" that I
shall not consider here because they are not relevant to the line of critique I
am developing. It should be pointed out, however, that the classic definition of
substance is not an arbitrary construction of philosophers' fancy. It is rooted
in reality as Connell's book points out.

17There are also significant
implications of the property-thing view for end of life ethics. See J. P.
Moreland, "Humanness, Personhood, and the Right to Die," Faith and Philosophy Jan. 1995): 95-112; J. P. Moreland, Stan Wallace, "Aquinas, Locke
and Descartes on the Human Person and End-of-Life Ethics," International
Philosophical Quarterly35 (Sept. 1995): 319-30.

21I set aside debates about
the exact nature of secondary causality (e.g. disputes over occasionalism and
alternative accounts) because the distinction between primary and secondary
causality will still be functionally and epistemologically significant
irrespective of the exact nature of the metaphysical account of the difference
between them because whatever else one wants to say here, secondary causality
will be God's usual way of acting and the laws of nature will be regular and
normal here (regardless of whether they are deterministic or probabilistic) and
primary causality will be God's unusual way of acting that could be
epistemically detected due to the contrast in this type of action compared to
the regular, usual sequences of events that constitute secondary causality.

24Some libertarians allow
for the existence of free acts that are not done for any reason at all, e.g.,
freely moving my hand back and forth or looking at one thing and then another
(where these acts are not caused by, say, a nervous twitch or a sudden noise).
Spontaneity is the name for non-rational, bare exercises of free will. But there
libertarians agree with the fact that a crucial class of human actions are those
done for certain reasons, so there is still an important area of debate between
libertarians and compatibilists about the role of reason in free choices.
Liberty is the name for this class of cases of free will.

26Richard Bube claims that a
scientific description is deterministic if it can predict a future state from a
present one and chance if it can only predict the probability of a future state.
See Putting It All Together,22-26. Moreover, such descriptions must be
one or the other. Now Bube thinks that these observations raise a paradox about
human responsibility. Such responsibility is hard to square with determinism
(how can I be responsible if determined) yet it also seems to require
determinism (how can a responsible choice exist without being described in a
definite cause [the basis of the choice] and effect [the result of the choice]
sequence). On the other hand, responsibility is hard to harmonize with chance
which seems to be required for responsible action yet chance is utterly random.
Bube's solution to the problem is simply to assert without adequate
justification that scientific descriptions of determinism or chance do not
entail determinism or meaninglessness as world views and that the two types of
descriptions can be complementary. However, if these descriptions are true, then
anything else we would say at a different level of description could not
contradict what is said at the scientific level. I think Bube misses this point
because his definitions of determinism and chance are epistemological and not
ontological. Unfortunately, epistemological definitions confuse the real issues
of freedom and responsibility. For example, epistemological determinism in
Bube's sense is neither necessary nor sufficient for ontological determinism.
Moreover, Bube fails to see that the real issue is the nature of agency and that
libertarian freedom is a third (and more adequate) option that renders his
dilemma incomplete.

32When it comes to
miraculous actions by God, Richard Bube admits that no scientific descriptions
can be given of such acts. See Putting It All Together. 25-26, 65-70. Now
this would seem to require a libertarian view of such acts; otherwise, they
would have complementary scientific descriptions. Yet Bube claims that such
miraculous acts cannot figure into scientific practice. Why? Because in such
acts, there is no scientific mechanism available for scientific description and,
therefore, primary causal miracles are not susceptible to scientific
investigation. It should now be obvious what is wrong with this clam: Scientific
investigation does not limit itself to descriptions, and a primary causal
act of God could figure into scientific methodology in the three ways mentioned
above, even though such acts themselves cannot be given a scientific
description.